Method of treating hydrocarbon oils



UNITED STATES PATENT OFFICE.

ALEXANDER S. BAMAGE, OF DETROIT, .MICHIGAN, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO BOST'APH ENGINEERING CORPORATION, OF DETROIT, MICHIGAN,- A.

CORPORATION OF NEW YORK.

METHOD OF TREATING. HYDROCARBON OILS.

No Drawing.

.of which the following is a specification.

In a copending application Serial No. 160,223, filed herewith, I have described a method of refining hydrocarbon mixtures containing olefines, said method comprising treating the mixture with a relatively small proportion, say one-half to two per cent by weight, of strong sulfuric acid, whereby a tarry precipitate containing hydrolyzable sulfuric acid derivatives of the defines is formed, and then hydrolyzing this precipitate by acting thereon with water, usually in association with an alkaline reagent. The hydrolysis yields bodies of the alcohol type and the subsequent distillation of the neutralized oils yields directly and without material losses a @ihparatively sweet smelling distillate utilizable as motor spirit and for other purposes.

The present method is a modification of the foregoing, and is more particularly applicable to such fractions or distillates as consist chiefly or largely of olefines or mixtures of olefines with aromatic compounds. Such distillates are obtainable for example in the practice of the process described and claimed in my Patent No. 1,224,787, patented May 1, 1917. The invention is not' however limited to these particular mix- .tures, but is applicable to any hydrocarbon mixture containing olefines whether produced by the cracking or catalytic decomposition of oils or otherwise.

According to the present method, I agitate such mixtures with a relatively large proportion-of sulfuric acid, and thereafter hydrolyze the resulting tars. By way of illus-.

tration, I may introduce 60-66 B. sulfuric acid into the oil, the acid being added slowly, with agitation, and with suflicient cooling to avoid loss of benzol 'or other volatile hydrocarbons by distillation. "Thistreatment results in the abundant formation of a tarry precipitate which comprises, among other products, hydrolyzable sulfuric acid derivatives of the olefines. As an em- Speeification of Letters Patent.

Application filed April 6,

Patented Feb. 28, 1922.

1917. Serial No. 160,224.

pirical rule, the amount of acid may be approximately fifty per cent by weight of the olefines in the mixture; that is, a dis-.

tillate containing fifty per cent of olefines would receive an addition of abouttwentyfivtzl per cent by weight of 66 B.- sulfuric aci Water is now added with stirring, in quantity sufficient to effect the substantially complete hydrolysis of the tar, as indicated by its disappearance, leaving a mixture of oily and aqueous liquids which stratify when the agitation is stopped. An amount of Water representing about ten times the volume of acid employed will usually suffice to accomplish the hydrolysis. Preferably, a suitable neutralizing agent, as lime or soda-ash, is added with the water, since the hydrolytic decomposition of the sulfuric acid derivatives of the olefines is thereby accelerated and rendered more complete.

While the chemical reactions occurring during the process are undoubtedly exceedingly complex, these reactions include the formation of bodies of the alcohol type. For example, amylene existing in the original oil yields,'with the sulfuric acid, products which upon hydrolysis "form .amyl alcohol, which dissolves in the oil, and to a relatively very small extent in the aqueous acid. Reactions ofa similar type occur with the other olefines. I

The above-described mixture of oil and aqueous acid may be permitted to settle, the

acid drawn off, and the oil containing the I .like manner. Preferably, however, as mentioned above, the neutralizing agent is introduced together with the water serving for the hydrolysis.

As a specific example of the practice of the process, a fraction prepared by passing hydrocarbon vapors over iron oxid in the manner disclosed in my Patent No. 1,224,7 87 above referred to, and boiling entirely beuct, and the mixture wasv then carefully fractionated. This fractionation yielded, by

volume,-

Under 78 C 1.71% 78-85 o 9.40% 8595 C 3.16% 95-105 C 1.90% 105120 G 4.27% 120150 C. 5.40% 150200 C 4.61% 200 225 o "13.42% 225-250 C s 21.35% 250275 C 7.70% 275-300 C 3.11% Over 300 C. 17.10% Loss"...- 6.87%

Total 100.00

Of the foregoing fractions those up to 150 C. consist largely of aromatics and alcoholic bodies. The fraction from-150 to 200 C'is composed chiefly of terpenes and xylol. The fractions above 200 C. comprise unidentified bodies, and the fraction above 275? C. constitutes a lubricating oil of high quality and low freezing-point. The products derived from the olefines by polymerization are not further affected by sulfuric acid, but are nitratable.

It will be observed that the treatment has resulted in a very strong polymerization of the original material, with the result that less than fifteen per cent of the product boils within the temperature limits of the original distillate. It will be observed furthermore that this polymerization has proceeded to such an extent that some 20 per cent of the product is an oil of lubricating grade.

According to the present invention it becomes possible to accomplish a sharp separation between aromatic bodies and olefines of similar boiling-point, a separation which has heretofore presented serious difiiculties. The amount of sulfuric acid used is chosen primarily with reference to its action upon the olefines, and is in practice suflicient to act upon all or substantially all ofthe olefines present, transforming them in part into sulfuric acid derivatives, and in part, presumably by polymerization, into products whose boiling-point is above the range of boiling-points of the aromatic substances. These last-named substances, bein unafl'ected by the sulfuricacid, are direct y recoverable by distillation in a state of substantial purity. In recovering aromatics by this tar should be drawn off and separately hydrolyzed and distilled, in order that the aromatics may not be associated with low-boiling alcohols resulting from the hydrolysis.

The statement in certain claims that the sulfuric acid is used in proportion suflicient to transform the olefines of the oil has reference' to both types of transformation mentioned above, that is to say, the polymerization and the formation of the correspondin hydrolyzable sulfuric acid derivatives. W ere reference is made to effecting hydrolysis of sulfuric acid derivatives by means of water, it is to be understood that the use of water containing dissolved or suspended alkaline reagents is included.

I claim 1. A method of treating hydrocarbon oils rich in olefines, which consists in reacting thereon with strong sulfuric acid in sufficient proportion to transform the bulk of the ole nes into high-boiling bodies, with coincident formation of sulfuric acid derivatives of olefines, and effecting a separation of these products by dissolving and hydrolyzing said sulfuric acid derivatives and distilling ofi and recovering the volatile products of the hydrolysis, 1

2. A method of treating hydrocarbon oils rich in olefines, which consists in reacting thereon with strong sulfuric acid in suflicient proportion to transform the bulk of the olefines into high-boiling bodies, with coincidentformation of sulfuric acid derivatives of olefines, and effecting a separation of these products by dissolving and hydrolyzing said sulfuric acid derivatives in presence of the oil, and distilling the oil together with the organic products of hydrolysis dissolved therein.

3. A method of treating hydrocarbon oils rich'in olefines, which consists in reacting thereon with strong sulfuric acid in the proportion of about fifty per cent by weight of the olefines present, thereby transforming the bulk of the olefines into high-boiling.

bodies, with coincident formation of sulfuric acid derivatives of the olefines, and effecting a separation of these products by mixing the reaction roduct.w1th suflicient water to yield therewith a substantially clear solution with coincident hydrolysis, and distilling oil and recovering the volatile products of the hydrolysis. v

4. A method of treating hydrocarbon oils rich in olefines, which consists in reacting thereon with strong sulfuric acid in the'proportion of about fifty per cent byweight of the olefines present, thereby transforming the bulk of the olefines into high-boiling bodies, with coincident formation of sulfuric acid derivatives of the olefines, and effecting a separation of these products by mixing the reaction product, in presence of the oil, with 65 method, it is desirable that the sulfuric-acid sufiicient water to dissolve said precipitate with coincident hydrolysis, and distilling the oil. together with the volatile products of the hydrolysis dissolved therein.

A method of treating hydrocarbon mixtures containing olefines and aromatic bodies, which consists in reacting thereon with strong sulfuric acid in proportion sufficient to transform substantially all of the olefines,

withdrawing the resulting tarry material, and fractionally separating the aromatic bodies from the high boiling point bodies reisiulting from the polymerization of the olenes.

In testimony whereof I afiix my signature.

ALEXANDER S. RAMAGE. 

